[OSM-dev] Live Database Copy of Planet File

[Peter Childs]

2009/11/5 Timo Juhani Lindfors <timo.lindfors at iki.fi>

> Peter Childs <pchilds at bcs.org> writes:
> > Does anyone know where I can find some "simple" instructions on how to
> > create a live copy of the planet file.
>
> I would like to do this too to provide a local mirror.  Last time I
> tried to do this I understood that this can't be done since the 0.6
> style diffs do not have enough information to create 100% identical
> copy. Is this still correct? I think the problem had something to do
> with changesets not being atomic.
>
> -Timo
>

Hmm I'm guess that would be caused by the use of timestamps and missing half
started transactions when the diffs is created...

There should be some way of converting the Postgres WAL into diffs but when
ever I suggested it on the postgres boards (and this was a few years ago
now) it was always condemned as a silly pointless idea..... My view is that
WAL could be used for a whole bunch of forensics and replication to other
database formats as well as PITR.... Currently all you can do in postgres is
roll your database back and then step forward and play spot the difference.
you should be able to turn the WAL into a human readable format....(Enough
Postgres Theory)

Peter.
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